THE OPTIMAL DESIGN OF THE 40.00-57 DUAL PURPOSE ORTHOTROPIC SHELL UNDER UNCERTAINTY CONDITIONS DESIGN

Problem statement. A feature of the modern technical systems’ design is that deterministic approaches dominate, while consideration of uncertainty can provide a more adequate representation of the research object in the appropriate calculation scheme, mathematical model. The consideration of uncertainties becomes especially relevant in the modeling of complex technical systems, where uncertainties can be quite abundant and the uncertainties themselves can be of different nature, namely stochastic, rough, fuzzy, or even combined. It is advisable to check whether the system is tolerant to uncertainties. This work is devoted to the construction of methods for the optimal design of the new rubber-cord shell 40.00-57 in the conditions of the fuzzy initial data. For a deterministic approach a special mathematical model can be used to calculate the output parameters. The mathematical model developed by Prof. E. Kvasha, at one time was truly revolutionary, because for the first time in the world the contact problem of the interaction of an elastic base with a layered orthotropic shell, which is part of a complex technical tire system, was solved. The main drawback, which could not be overcome by varying the input parameters, remained the uneven resource of the shell frame elements. So, variant design has shown its insufficient efficiency for such complex technical systems. The purpose of the research is to suggest a model and methods of optimal design for optotropic rubber-cord oversized shells under the conditions of real factors of uncertain nature. Conduct methods testing and design a new construction of tire 40.00-57 for civilian and military purposes. Conclusion. The authors proposed models and methods of optimal design of orthotropic rubber-cord shells under the condition of fuzzy data. Approbation of the symbiosis of Monte Carlo methods and the method of local variations for finding the optimal geometry of the shell was conducted. For new 40.00-57 tire shape, the difference between the largest frame resource and the smallest resource of the tire’s elements was about 18 %. Such a result could not be achieved by variant design. The temperature distribution in the cross-section of the tire under conditions of operation for 8 hours at an ambient temperature of 37 0C does not exceed the value of 110 0C, at which the thermal destruction of the rubber-cord material begins.